Fire-box for locomotive-boilers.



` PATENTBD Nov. 5, 1907.

' L M. MGGLELLON. PIRE B0X POR LOC'OMGTIVE BOILERS.

APPLICATION FILED DBO. 20, 1906.

JAMES M. MCCLELLON, OF EVERETT, MASSACHUSETTS.

FIRE-BOX FORv LOCOMOTIVE-BOILERS.

Specification of Letters Patent.

Patented Nov. 5, 1907.

Application filed December 20, 1906. Serial No. 348,790;

To all whom it may concern.'

Be it known that I, JAMES M. MCCLELLON, a citizen of the United States,residing at Everett, county of Middlesex, and State of Massachusetts,have invented an Improvement in Fire-Boxes for Locomotive-Boilers, ofwhich the following description, in connection with the accompanyingdrawing, is a specification, like letters on the drawing representinglike parts.

This invention relates to fire-boxes and has for its object to provide anovel tire-box which will have a greatly increased heating surface, andone on which repairs can be readily made, and also one which can beapplied to any ordinary construction of boiler.

The particular features of the invention will be more fully hereinafterdescribed and then pointed out in the claims.

In the drawings, Figure 1 is a vertical section transversely through theiire-box of a locomotive showing one embodiment oi my invention; Fig. 2is a detail view of one form of lower drum.

The lire-box herein shown has at each side near its bottom a lower drum,said drums being designated by 3 and 4, which extends the length of thefire-box, and at the top above the combustion chamber are steam andwater spaces which are connected with the lower drums by means of watertubes 5 and 6.

In the present embodiment of my invention the water space at the top ofthe combustion chamber is formed between two sheets 7 and 8, the innersheet 7 constituting in effect a sort of crown-sheet. At the sides ofthe re-box are water legs 9 and 10 each formed by two sheets 1l and 12which extend from the lower drum upwardly. The sheets 11 and 12 formingthe two side water legs are preferably bent inwardly at their centralportions, as at 13, for reasons which will more fully hereinafterappear.

The sheets 11 and l2 forming each water leg are both rivetedto the outerside of the corresponding lower drum, as at 14, and are also nippledthereto, as at 15, 'whereby a ree'communication between the water legsand the drums is established.

The upper ends ot' the'sheets 11 and 12 are shown as bent inwardly andriveted to the upper sheet S, as'at 16, and the crown-sheet 7 may haveits edges turned upwardly and riveted to the inner' sheet l2 at thesides of the tire-box as at 70. The sheets 11 and 12 at each side of thenre-box will, of course, be stayed by suitable stay-bolts 17 in usualmanner, and each inner sheet l2 is provided with a plurality ofperiorations 19 at its upper edge which form a communication between thewater space above the crownsheet and the water legs.

Below each oi the lower drums 3 and 4 at each side is a mud ring 2lwhich has communication with the drums through suitable nipples 22. Thismud ring is formed by bending a vsheet into substantial U-shape.

The space above the crown-sheet 7 is divided by two longitudinalpartitions 23 into two side spaces 24 and 25 and a center space 26 whichconstitutes a steamdome, said partitions 23 having apertures 27 thereinwhich furnish communication between these various chambers.

The water-tubes 6 extend between the lower drum 4 and the chamber 24,and the water-tubes 5 extend between the lower drum 3 and the chamber25, said water-tubes crossing each other, as shown in Fig. l. In thedrawings this Ere-box has been shown in connection with an ordinaryboiler-shell 28 which has lues 29 extending therethrough, and in orderto get the greatest amount oi heat out of the hot gases in transit tothe flues 29, it is of advantage to so arrange the water-tubes that theycover substantially the full iront area oi the flue-sheet at the back ofthe re-box. lt is, however, important that the water-tubes should not beso positioned as to reduce the grate area or to intertere with properfiring. To accomplish both these objects, I propose to arrange the loweredge of the water-4 tubes very closely together, butto spread them attheir upper end so that they will cover as much as possible of the irontof the flue-sheet. In this embodiment of my invention the water-tubes oieach row are arranged closely together and are staggered where theyenter the lower drum, but are separated considerably and are preferablyarranged in a single plane at their upper ends.

The drawing-in oi the sheets 11 and 12 is for the purpose of eliminatingas far as possible any space between the upper ends of the water-tubes 6and the lower ends ofthe water-tubes 5.

In order to extract the greatest number of heat units from the hot gasesit is desirable to impede to some extent their progress toward the fluesfor if they pass into the lues 29 too rapidly, the interval of timetaken in so passing is not sufficient to permit them to yield up thegreatest amount of heat. Accordingly I stagger the Water-tubes 5 of onerow relative to those of the next succeeding row and do the same withthe water-tubes 6. By thus arranging the water-tubes and by drawing inthe sheets 1l and 12 at the sides of the boiler, practically no space isprovided through which the hot gases can pass directly to the flues 29without coming in contact with the water-tubes. With this constructionthe hot gases are brought continuously in contact with the water-tubesuntil they pass to the lues 29 and a maximum amount of heat units canthus be delivered to the water Within the water-tubes.

It will be understood, of course, that the sheets 7 and 8 may be stayedin any suitable way if this is found to be necessary.

It will be noted that both the inner and outer sheets 7 and 8 areriveted to the sheet 12 so that said sheet 12 at its upper end acts as ameans for tying together and staying said two upper sheets. It will benoted also that the outer sheet 8 is a true section of a cylinder, whilethe inner sheet 7 is flattened somewhat on the sides. The object inmaking the outer sheet of this shape is so as to get the greatestpossible strength from the sheet without the need of staying it, and theobject o flattening the ends of t-he inner sheets S is .t0 make saidsheet of such a construction that the Watertubes 5 and 6 may extendthereinto at right angles thereto.

It will be noted that the joints between the inner sheet 7 and thesheets 12 are so situated that the fire does not come in contacttherewith, and this is true oi the joints between the sheets 11 and 12and the drums 3 and 4. In fact there are no joints at all in the boilerwith which the lire directly comes in Contact.

If desired the lower drums 3 and 4l may be provided with man-holes forfacilitating the removal of any oi the water-tubes or their replacement.Sucha construction is shown in Fig. 2, and in said ligure, each drum ismade of two parts, an inner part 30 ot sheet metal which issubstantially U-shape, and into which the watertubes 5 are expanded, andthe outer part 3l which may be cast metal, said outer part overlappingat its edges and being riveted to the sides of the sheet 30. The sheet30 is that which comes directly in contact with the lire, and this maybe made of better material than the outer section 31 which is not soexposeddirectly to the flame. The cast metal section 31 may be providedwith man-holes 32 closed by a suitable man-hole cover 33, and it may bestiliened by suitable ribs 34 extending transversely thereof. In otherrespects the invention shown in Fig. 2 is similar to that shown in Fig.1.

Although I have herein shown this construction as embodied in a lire-boxot a locomotive, it will be obvious that the same essential features ofconstruction might be embodied in a stationary or marine boiler, andtherefore I do not wish to be limited to a locomotive lire-box.

Having described my invention, what I claim as new and desire to secureby Letters Patent iszl. In a boiler of the locomotive type, thecombination with a boiler shell having dues therethrough of a fire-boxat one end of the shell, said fire-box having separated inner and outersheets at its top said inner sheet being outwardly curved, alongitudinally-extending water space at each side of the fire-box nearthe bottom, and water-tubes connecting each water space with the spacebetween the inner and outer sheets, the water-tubes extending from onewater space crossing those that extend from the other, and saidwater-tubes covering substantially the entire inner sheet.

2. A fire-box having inner and outer sheets at the top the inner sheetbeing outwardly curved, a longitudinally extending drum at each sidethereof at the bottom, a water-leg at each side connecting thecorresponding drum with the space between the two sheets, andwater-tubes connectingeach drum with said space, the water-tubes thatextend from one drum crossing those that extend from the other drum.

3. A ire-box for a locomotive boiler having separated inner and outersheets at its top the inner sheet being outA Wardly curved, alongitudinally extending drum at each side thereof at the bottom, andwater-tubes connecting each drum with the`space between the inner andouter sheets, the water-tubes extending from one drum crossing thosethat extend from the other drum, and the watertubcs that extend fromeach drum being nearer together at their lower ends than at their upperends.

l. A lire-box for a locomotive boiler having separated inner and outersheets at its top, a longitudinally extending drum at each side thereofat the bottom, and banks or nests of water-tubes connecting each drumwith the space between said sheets, each nest of tubes havingfastaggered arrangement where they enter' the drum and being insubstantially the saine plane where they enter the inner sheet, and thetubes which extend from one drum crossingthose which extend from theother drum.

5. A fire-box having at its top two sheets, and near its bottom at eachside a longitudinally extending drum, a water leg connecting each drumwith the space between the sheets, a plurality of banks of water-tubesconnecting each drum with said space, the water-tubes of each bankhaving a staggered arrangement at the lower end and being in the sameplane at the upper end, and the watertubes of adjacent banks having astaggered arrangement, the water-tubes extending from one drum crossingthose extending from the other drum.

G. A tire-box having two separated sheets at its top, a longitudinallyextending drum at each side near the bottoni, two separated sheets ateach side connecting the drum with the sheets at the top, said sheetsfrom the sides extending inwardly from both the top and the bottom, andwater-tubes connecting each drum with the space between the sheets atthe top of the boiler.

7. A lire-box having two separated sheets at its top, a longitudinallyextending drum on each side near the botA toin, two separated sheets ateach side connecting the drum with the sheets at the top, said sheets atthe side extending inwardly from both the top and the bottom, andwater-tubes connecting each drum with the space between the sheets atthe top of the boiler, the water-tubes extending from one drum crossingthose extending from the other drum.

8. A fire-box for a locomotive boiler having two separated sheets at thetop, a longitudinally extending drum at the bottom on each side,watertubes connecting each drum with the space between the sheets at thetop, the Watertubes extending,l from one drum crossing those extendingfrom the other drum, and separated sheets at each side of the boiler,the upper and lower portions of each sheet being inclined inwardlytoward the center of the lire-box.

E). A boiler having a water space at the top, a longitudinally extendingdrum at each side near the bottom, and water-tubes connecting each drumwith the space at'the top of the boiler, each drum being formed of twoU-shaped parts connected together along opposite sides of the drum, theportion on the inner side to which the watei'tubes are v connected beingformed of wrought metal and the outer portion being formed of castmetal.

l0. A boiler having a water space at the top, a drum at each sidethereof at the bottom, Water-tubes extending from each drum to the spaceat the top of the boiler, and separated sheets forming a water leg atthe sides of the boiler, said sheets on each side of the boiler bothbeing riveted to the outside of the corresponding drum.

11. A boiler having a water space at the top, a drum on each sidethereof near the bottom, water-tubes extending between said drums andthe water space, water legs at each side of the boiler connecting thedrums with the space at the top of the boiler, and a mud-ring below thedrums.

12. A boiler having two separated sheets at the' top forming a waterspace between them, and two separated sheets at each side of the boilerconstituting a water leg, the limer sheet at each side of the boilerbeing riveted to both the inner and outer sheets at the top of theboiler.

3. A boiler having two separated sheets at the top forming a water spacebetween them, and two separated sheets at each side ot' the boilerconstituting a water leg, the inner sheet at each side of the boilerbeing riveted to both the inner and outer sheets at the top of theboiler, and both sheets at each side of the boiler being riveted to thetop sheet.

14. A boiler comprising two separated sheets at its top forming a waterspace between them, the outer sheet being curved to the arc of a truecircle, and the inner sheet being tlattened on its sides, a drum at eachside of the boiler, and water tubes connecting each drum to the at-'tened portion of the inner sheet on the opposite side of the boiler,the water-tubes which extend from one drum crossing those which extendfrom the other.

15. A fire-box for a locomotive boiler having separated inner and outersheets at its top, the inner sheet being outwardly curved, alongitudinally-extending drum at each side thereof at the bottom, andwater-tubes connecting each drum with the space between the inner andouter sheets, the waterftubes extending from one drum crossing thosethat extend from the other drum, and the watertubes that extend fromeach ydrum being spread at their upper ends to cover substantially theentire area of the inner sheet.

16. A boiler having a water space at its top and a 1ongitudinally-extending drum at each side thereof at the bottom,water-tubes extending from each drum to the space at the top of theboiler, and separated sheets forminf,V a water leg at each side of theboiler, the lower ends of the sheets for each water leg overlapping eachother and being secured to the outside of the corresponding drum.

17. A tire-box having a water space at its top, alongitudinally-extending drum at each side at the bottom, two separatedsheets at each side connecting the drum with the space at the top andforming between them a water leg, said sheets being bent inwardly attheir central longitudinal median line, and water-tubes connecting eachdrum with the space at the top.

1S. A tire-box for a locomotive boiler having inner and outer sheets atthe top, the inner sheet being outwardly curved, alongitudinally-extending water space at each side near the bottom, awater leg at each side connecting the corresponding water space with thespace between the two sheets, and water-tubes connecting each waterspace at the lower side of the drum with the space between the sheets atthe top of the drum, the water-tubes that extend from one water spacecrossing those that extend from the other.

19. A re-box for a locomotive boiler having inner and outer sheets atthe top, the inner sheet being outwardly curved, alongitudinally-extending water space at each side near the bottom, aWater leg at each side connecting the corresponding water space with thespace between the two sheets, and water-tubes connecting each waterspace at the ,lower side of the drum with the space between the sheetsat the top of the drum, the water-tubes that extend from one water spacecrossing those that extend from the other, and the water-tubes thatextend from each water space being nearer together at their lower endsthan at their upper ends.

20, A fire-box having a chamber at its top and a longtudinally-extendingwater space at each side near the bottom, two sheets at each sideforming between them a water leg which connects the space at the sidewith the chamber at the top, said sheets extending inwardly from boththe top and the bottom.

2l. A re-box having a chamber at its top and a longitudinally extendingwater space-at each side neat the bottom, two sheets at each sideforming between them a water leg which connects the space at the sidewith the chamber at the top, said sheets extending inwardly from boththe top and the bottom, and water-tubes connecting each water space withthe chamber at the top.

2:2. A fire-box having a water space at its top and alongitudinally-extending water space at each side at the bottom, twoseparated sheets at each side forming a water leg connecting the spaceat said side with the water space at the top, said sheets each beingbent inwardly at their central longitudinal median line, and water-tubesconnecting each longitudinally-extending water space with the space atthe top of the lire-box.

In testimony whereof, I have signed my name to this specification, inthel presence of two subscribing witnesses.

JAMES M. MCCLELLON. Witnesses: LotIs C. SMITH, BERTHA F. HnUsER.

